exec: Restrict 'cpu_ldst.h' to TCG accelerator

"exec/cpu_ldst.h" is specific to TCG, do not allow its
inclusion from other accelerators.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240418192525.97451-6-philmd@linaro.org>
diff --git a/include/exec/cpu_ldst.h b/include/exec/cpu_ldst.h
index 5b99666..f3c2a3c 100644
--- a/include/exec/cpu_ldst.h
+++ b/include/exec/cpu_ldst.h
@@ -1,5 +1,5 @@
 /*
- *  Software MMU support
+ *  Software MMU support (per-target)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -62,6 +62,10 @@
 #ifndef CPU_LDST_H
 #define CPU_LDST_H
 
+#ifndef CONFIG_TCG
+#error Can only include this header with TCG
+#endif
+
 #include "exec/memopidx.h"
 #include "exec/abi_ptr.h"
 #include "exec/mmu-access-type.h"